Split nut for use on a machine tool slide rest controlled by a screw and to an operating device for the same



June 15, 1965 F. VALLIERE 3,188,897

- SPLIT US N A MACHINE TOOL SLIDE BBS CONTROLLED A SC W AND TO A OPERATING DE E F0 HE SAME Filed March 1, 1962 2 Sheets-Sheet 1 & /5 l6 9 V June 15, 1965 P. F. DE VALLIERE 3,188,897

SPLIT NUT FOR USE ON A MACHINE TOOL SLIDE nnsw CONTROLLED BY A scREw AND TO A" OPERATING DEVICE FOR THE SAME 4 Filed March 1. 1962 2 Sheets-Sheet 2 United States Patent 3,188,897 SPLIT NUT FOR USE ON A MACHINE TOOL SLIDE REST CONTROLLED BY A SCREW AND TO AN OPERATING DEVICE FOR THE SAW Pierre Franeois de Valliere, 14 Ave. de Bretteville,

' Neuilly-sur-Seine, France Filed Mar. 1, 1962, Ser. No. 176,525 Claims priority, application France, Mar. 7, 1961, 854,813, Patent 1,290,935 12 Claims. (Cl. 8223) I This invention relates to a split nut particularly intended for controlling the travel of a machine tool slide rest, through the medium of a screw and more specifically a feed screw, and the invention relates further to a control means providing interlocking between the act of engagement of said nut on its screw and some other function such as the mechanical feed on a lathe, by operation of a single lever associated with locking means.

In accordance with this invention, the split nut has half nuts portions which are controlled by a shaft and guided along a pair of columns, each column of which is rigid with a respective half nut and displaceably and adjustably mounted in the other half nut to allow cross-wise centering of said half nuts.

In a preferred embodiment, the ends of said columns are mounted in eccentric hearings in the slide rest.

The control shaft is preferably connected to each halfnut through links rigid with said half-nuts and co-operating, through the medium of corresponding retainers, either with eccentrics rigid with the operating shaft, or with cams inside said retainers, which retainers then act as frames.

The control shaft is preferably hollow to enable a second control shaft to extend through it, for controlling mechanical feeds, for example. The heads of the outer shaft and the inner shaft are each rigid with projections, between which is mounted, in freely rotatable manner, a ring which is rigid with an operating lever.

Each of said projections is provided with a notch and these two notches co-operate with a stirrup-shaped sliding lock means which surmounts a key mounted slidably in the ring, thereby providing an interlock that enables one of said projections to be clamped immovably by said lock while the other is freed, and which further enables the free projection to be rigidly united with said ring by means of said key.

A machine tool equipped with such a device provides improved accuracy in regard to the position of the nut in the slide rest, together with a simpler form of operation which combines two functions that can be rendered operative by means of a single lever.

The description which follows with respect to the accompanying drawings, offered by way of example only and not of limitation, will give a clear understanding of how the invention may be carried into practice.

Referring to the drawings filed herewith:

FIG. 1 is a diagrammatic cross-section of a slide rest with its nut engaged on the feed screw;

FIG. 2 is a similar sectional view, restricted solely to the nut in the open position;

FIG. 3 is an alternative embodiment of a portion of FIG. 2;

FIG. 4 is a diagrammatic longitudinal section View of the interlock control;

FIG. 5 is a front elevation view of the control and its locking means; and

FIG. 6 is a further sectional view, taken through a plane perpendicular to that of FIG. 4.

Referring to FIG. 1, there is shown thereon a machine tool feed screw 1 which is adapted to displace a slide rest 2 by means of a split nut consisting of two half-nuts 3a 3,l3%,89,7 Fatented June 15, 1965 ice and 3b, each half-nut being rigid with a column 4 slidably mounted in end supports and in a bearing extending through the other half-nut. The said supports consist of bearings 5 and 6 rotatably mounted in the casing 2, the supporting bores for the columns being eccentric with respect to the supporting bores of the bearings 5, 6. In the drawing, the bearing 5 is illustrated, with its locking bolt 7 screwed into the wall of the casing 2 and clamping the corresponding hearings in the selected eccentric position.

In this manner, each half-nut may be adjusted longitudinally with respect to the screw 1, thereby providing desired centering in height as well as in the direction of travel of the slide rest of which the casing 2 forms a part.

The lower part of each half-nut is provided with a slot 8 into which extends a link 9. Each link 9 is mounted on the eccentric stub 10 of a pin 11 the other end of which has a square head for angular adjustment, said pin being adapted to be locked by a screw 13 threaded in a bore in the respective half-nut.

In this manner, each link may be adjusted in position with reference to the corresponding half-nut.

The inner extremity of each link 9 forms a retainer 14 adapted to co-operate with an eccentric 15. The two ec centrics 15 are rigid with a hollow shaft 16, and the corresponding two eccentrics are .angularly spaced by degrees. The said shaft 16 extends through a half-nut and encircles a shaft 17 which passes through the casing 2. The hollow shaft 16 carries a projection 18 keyed thereto, while the shaft 17 carries a projection 19 which is keyed to it and retained in the end position by a countersunk head screw and a washer.

Between the aforementioned two projections is inserted a ring 20 which is rigid with an operating lever 21, said ring being freely rotatable between the projections. On each projection 18 and 19 is provided a notch 22 into which is engageable a respective branch 23 of a lock 24 slidably mounted on a stud 25, which stud is fixed to the wall of the casing 2, parallel to the common axis of the shaft 1'7 and the hollow shaft 16. The two branches 23 of the lock 24 straddle a notched key 26 which is inserted into a hole in the ring 20 and retained therein by a peg 27 projecting into the notch of said key.

Fitted as hereinbefore described, the lock 24 is susceptible of occupying any of three different positions, as follows:

(1) In the fully retracted position, more clearly illustrated in FIG. 4, the lock 24, through its branch 23, immovably clamps the projection 19 and hence the shaft 17. The key 26 is thrust into the notch in the projection 18, so that the ring 20 and the lever 21 are made rigid with the hollow shaft 16. Thus, the lever 21 will allow the half-nuts 3a and 3b to be opened or closed about the feed screw 1. Such opening and closing are obtainable by action of the studs 10 in response to rotation of the pins 11. FIG. 2 clearly shows that only about one quartertum of the hollow shaft 16 will open or close the half nuts. The plate 18 is so keyed as to cause the notch in the projection to locate opposite the corresponding branch of the lock 24 when the nut is open.

(2) In the midway position of the lock 24, both projections are locked by the branches 23 of the lock 24, thereby locking all the movements in the neutral position.

(3) When the lock 24 is in the withdrawn position, the projection 18 is rendered immovable, while the projection 19 is freed from the lock but made rigid with the ring 20 and its lever 21. In this position, the nut 3a, 3b is locked in the open position, and the lever is able, through the shaft 17, to control engagement and disengagement of the drive to a feed mechanism or the like.

The switch from any position to another compulsorily requires passage through the neutral point, which point V i 8. The combination as claimed in claim" 7 wherein the means for turning each pin includes a protruding engageable polygonal head at an end remote from the stub.

9. The combination as claimed in claim 3 wherein said control means further comprises a further shaft rotatably supported in theslide rest in coaxial relation within the first said shaft, an operating ring, a lever integral with said ring, a pair of projections each secured to a respective It is to be clearly understood that many modifications may be made to the specific embodiments described hereinabove, without departing from the scope of the invention. 7

What I claim is: v

1. In combination, a movable slide rest, a moving the slide rest and'a control device comprising a split nut supported on said sliderest and including'two half nuts which may be opened and closed for being respectively disengaged and engaged with said screw, a pair of column supports passing through saidhalf nutseach' secured to a respectivehalf nut while being slidable in the other half nut, eccentric bearing means adjustably sup ported in said slide rest and supporting the columns there-' in and control means for opening'and closing the half nuts. j

2. The combination as claimed in claim 1 wherein said eccentric bearing means comprises a rotatable ring having an eccentric bore supported for'rotation-in the slide rest and rotatably mounted on the columns at the ends thereof and means for locking'each ring in an adjusted angular position in the sliderest. i i

3. The combination as claimed in claim 1 wherein said control means comprises a pin securedin each half nut, a link rotatably supported on each pin, a shaft 'rotatably supported in the slide rest, and means supporting said links from said'shaft. I 1

4.- The combination as claimed in claim S'Wherein said means supporting said links includes eccentric stubs on said'shaft one for a respective link, each said link having an'opening in which a corresponding stub is retained 5. The combination as claimed in claim 4 wherein said 6. The combination as. claimed in claim 3 wherein said means supporting said links includes a pair of cams suptangular outline in which isaccommodated a respective cam.

7. The combination as claimed in claim 3 comprising means for turning each pin in'therespective half nut, each said pin including an eccentric stub onwhich the corresponding linkis rotatably supported such that the relative positions of said stubs and'said half nuts may be adjusted by turning the pins.

screw for a one projection is free.

shaft, said operating ring being rotatably supported betweens'aid projections and means for selectively engaging the operating ring with the projections for common rotation whereby rotation of the shafts maybe controlled by the lever. I 7 V 10. The combination as claimed in claim 9 wherein said means for selectively engaging the operating ring with the projections comprises a slidable lock supported from the slide rest for movement between extended and retracted positions and including branches for respectively engaging the projections such that in the retracted position one of the projections is engaged 'with the ring while the other projection is free while in the extended position the other of the. projections is engaged with the ring and, the said 11. The combination as claimed in claim 9 wherein the said means for selectively engaging the operating ring with the projection'comprises a key slidably'mounted in said ring, each of said projections being provided with a notch, a retaining peg situated'between said ring and said key, a lock engaging said key, a guiding stud'for said lock supportedfrom the slide rest, said lock being slidably mounted on said stud for movement in a direction parallel to the said shafts, two branches on said lock straddling said key, said branches and said key being aligned and slidable in said notches such that one of said branches in oneofsaid notches retains thecorresponding projection, as the other branch frees thenotch of the other projection, whereby said key is inserted in said freed notch,thereby interlocking said ring and said other proopenings and stubs have corresponding circular outlines.

. ported on said shaft, each link having an opening of reci jection.

' 12;The combination as claimed in claim ll wherein the opening of said split 'nut and a neutral position of the inner shaft corresponds to an aligned position of said notches and. of-said lock.

References (Iited by the Examiner AND EW R. JUHASZ, Primary Examiner.. WILLIAM w. DYER, 111., Examiner. 

1. IN COMBINATION, A MOVABLE SLIDE REST, A SCREW FOR MOVING THE SLIDE REST AND A CONTROL DEVICE COMPRISING A SPLIT NUT SUPPORTED ON SAID SLIDE REST AND INCLUDING TWO HALF NUTS WHICH MAY BE OPENED AND CLOSED FOR BEING RESPECTIVELY DISENGAGED AND ENGAGED WITH SAID SCREW, A PAIR OF COLUMN SUPPORTS PASSING THROUGH SAID HALF NUTS EACH SECURED TO A RESPECTIVE HALF NUT WHILE BEING SLIDABLE IN THE OTHER HALF NUT, ECCENTRIC BEARING MEANS ADJUSTABLY SUPPORTED IN SAID SLIDE REST AND SUPPORTING THE COLUMNS THERE- 